2639 A Curious Case of Abdominal Pain

Abstract

INTRODUCTION: Median arcuate ligament syndrome (MALS) is a rare condition where compression of the coeliac artery and ganglia by the median arcuate ligament results in gastrointestinal symptoms. Whilst 13–15% of the population exhibit radiological features of celiac artery compression, only a fraction is symptomatic. We present a case of a frail patient investigated for chronic abdominal pain that was ultimately attributed to MALS. CASE DESCRIPTION/METHODS: An 86-year-old lady presented with a two-year history of post-prandial nausea, abdominal pain and unintentional weight loss. She was an ex-smoker and denied any alcohol intake or NSAID use. Clinical examination was unremarkable. Initial lab workup was within normal limits and H. pyloriserology negative. An EGD demonstrated duodenal erosions and superficial ulcerations. A gastric emptying study was unremarkable. CT enterography and an MR angiography demonstrated focal narrowing of the celiac artery by the median arcuate ligament ( Figures 1 and 2 ). Vascular duplex demonstrated altered celiac artery velocities with respiration ( Figure 3 ). A provisional diagnosis of MALS was made. The patient underwent celiac plexus block (CPB) with which her symptoms resolved. She later underwent celiac plexus neurolysis and remains symptom-free. DISCUSSION: MALS is an uncommon diagnosis typically characterised by a triad of post-prandial abdominal pain, weight loss and abdominal bruit. There are currently no proven pathophysiological mechanisms though ischaemic and neuropathic mechanisms have been hypothesized. MALS is a diagnosis of exclusion and a difficult one to make given its rarity and lack of specific symptoms. The gold standard for diagnosis is with conventional angiography. Given our patient’s frailty, we opted for minimally-invasive radiological investigations and provocative physiological testing with CPB. The mainstay of management is with open surgical decompression but this is associated with high rates of post-operative complications and prolonged hospital stays. Celiac plexus neurolysis is an alternative option that could be considered in frail patients for both diagnosis and management. MALS is a rare but important diagnosis to consider in patients with chronic abdominal pain and proves to be a diagnostic challenge. Our case demonstrates the use of non-invasive investigations and provocative physiologic testing to diagnose MALS in a frail patient and highlights celiac plexus neurolysis as a treatment option.